论文部分内容阅读
采用原位水热法在铝合金AA5005表面制备镁铝层状双氢氧化物(LDH)涂层;利用X射线衍射、傅里叶红外、扫描电子显微镜以及能谱仪研究涂层的化学成分、表面形貌及物相;考察溶液p H值对形成LDH的影响。结果表明:当溶液p H值为10.0时,所得到的LDH涂层结晶最好。通过动电位电化学技术以及电化学阻抗研究水热反应时间对LDH涂层耐蚀性能的影响。随着水热反应时间的延长,涂层的耐蚀性提高,但当水热反应时间达到8 h时,再继续延长反应时间,其耐蚀性提高不明显。另外,还探讨了LDH涂层的耐蚀机理。
The Mg-Al layered double hydroxide (LDH) coating was prepared on the surface of AA5005 aluminum alloy by in-situ hydrothermal method. The chemical composition of the coating was studied by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and energy dispersive spectroscopy. Surface morphology and phase; study solution p H value of the formation of LDH impact. The results show that: when the solution p H value of 10.0, the LDH coating obtained the best crystal. The effects of hydrothermal reaction time on the corrosion resistance of LDH coatings were investigated by potentiodynamic and electrochemical impedance spectroscopy. With the extension of hydrothermal reaction time, the corrosion resistance of the coating increases, but when the hydrothermal reaction time reaches 8 h, the reaction time is prolonged to prolong the reaction time, and the corrosion resistance of the coating is not obviously improved. In addition, the corrosion mechanism of LDH coating is also discussed.